Worksheet 2 Answers
*Cough, cough* It sure is smoggy over Highway 401!

 (Measuring the environmental impacts)

• Naturally occurring greenhouse gases help regulate the planet's climate by trapping solar energy which warms the earth's surface.
  
  
• In 2004, transportation accounted for 26% of total greenhouse gas emissions.
  
  
• From 1990 to 2004, these transportation emissions rose 30%, or almost 45 megatonnes. Our growing dependence on road vehicles to move people and goods was the main factor.
  
  
• SUVs, pickups and vans have grown in popularity. From 2000 to 2005, the fleet of light automobiles fell by 1%, while the number of light trucks rose 26%. In 2005, average fuel efficiency for cars was 9.1 L/100 km; 14.0 L/100km for pickups, and 11.5 L/100 km for vans.